Gold alloy



- a citizen of the United States,

.10 socalled green go Patented Apr. 13, 1926.

UNITED s A THOMAS'ZP. SHIELDS, NEWYORK, N. Y.,

COQN'SISTING OF'THOMAS P. SHIELDS AND G. A.

ASSIGNOR TO SHIELDS 8t MOORE, A FIRM MOORE, OF NEW YORK, N. Y,

GOLD ALLOY.

No Drawing. Application filed July 6,

To all whom it may concern:

Be it known that LTHoMAs P. SHIELDS, residing .at New York city, 'New' York, have invented certain new and useful Improvements in Gold Alloys, of which the following is a specification;

The present invention relates to gold a1- loys and has for its special object to produce id as well as socalled yellow gold alloys, which alloys can be produced at a low price and in an efiicient manner.

A special object of the-invention is to produce a gold alloy oft-he character specified, which will melt at such temperatures as are readily secured by goldsmiths with the same heating appliances used in melting pure gold and its common alloys such as those ordinarily used'in making jewelry, etc. In my copending application, I describe alloys of the class above identified, and containing chromium as a constituent, but such alloys, especially when containing over. about 2% chromium are more difiicult to melt.

The invention will be described in connection with several specific examples, but it. is to be understood that the invention is not restricted to these specific examples.

' Inthe preferred form of the invention, I first preferably prepare an alloy of chromium, copper and zinc (with or without silver) in desired proportions, 'as given below (termed alloying alloy), to which I then add, while said alloy is molten a suiiicient amount of gold (e. g. fine gold or gold containing some alloying metals as commonly found in the market) to bring tual gold content upto say 40 to of the whole.

As examples of the give the following Example 1 Example 2."

parts to 2 parts chromium, 24 parts to 50 parts copper, 10 parts to 18 parts z nc.

' are then These alloys, in a molten state,

lted gold, as above stated, the

mixed with me p latter amounting to 40 to 60% of the entire alloying alloy I the total ac-.

of chromium,

1925. Serial-No. 41,874.

alloy to form finished alloys, say of the following composition. Preferably the chromium is not substantially over 1% and in all cases is less than 2% of the finished alloy.

. Example 3.

40% to 60% gold, together with 60 to 410% of an alloy consisting of 24 to 50 parts of copper, 10 to 35 parts of zinc, 00 to 15 parts ofsilver, 0.1to part of chromium.

I i 0 Example 4.

' 40% to 60% gold, together with 60 to an alloy consisting of .8 to 1 part of chromium, 20 to 50 parts of copper, 10 to 35 parts of zinc.

These alloys have most of the properties oi the other alloys of Serial No. 31,671. The difference is t at a part of the chromium is replaced by zinc.

I then can castthis alloy into desired shapes or can roll out the same into sheets or draw it into rods, wire or In compoundinw the final alloy from alloying alloy an gold which already contains substantial amounts of other metals, it is of course possible to take the latter into consideration when making up the alloying 'alloy, for that particular batch.

Itwill be understood that the presence of metals other than those above mentioned, in

small amounts in the-final alloy, is not pre-Q cluded. Such other metals, if present in substantial amounts may of course influence the properties of the alloy, to a greater or less extent. I

E xample 5.

about 58.3% of fine gold, 0.5% 2% of fine silver, 14% of zinc and 25.2%of copper. This produces an al-v loy which is relatively low in gold, but pos-' sesses the propert of not readily tarnishing, and this alloy wi 1 be found to have the desired green gold color and will have good working properties. It is fusible at about the same temperature as gold. This alloy is very cheap to produce, and can be readily worked with ordinary goldsmiths tools, and also can be readily enameled.

In this example, as in several of the other examples, the amount of silver can be greatly reduced, and if desired can be omitted altogether, and if it is desired'to decrease the I employ other forms.-

vcontain any of the metals of the amount of silver it is preferable to increase the amount of chromium somewhat.

Ewample v6.

40% of fine gold, 1% of chromium, of copper, 29% of zinc and no silver areemployed. Infthis alloy it is'noted" that the amount of gold is relatively low so that the alloy is cheaply produced, andis very suitablefor making u jewelry.

, In making up t 1e alloy, I preferablymix together the chromium, copper and zine (and silver if it is to be used) in about the proportion in which they are to exist invthe" final alloy. These metals'can be mixed together,

group, which have heretofore been used'in alloys ofthis general class, for the preven- 24 to 50 parts, and zinc 10 to 18 parts.

intermediate alloy consisting 'essen- :50 parts tion of tarnishing.

The metals of this group" the present-invention aresubstantially free ys produced .in accordance with from tendencyto tarnish, even in the form of jewelry about 10 to 14 carat.

["I claim 1. An intermediate alloy consisting essentially of:chromium 0.1 to 2 parts, copper 2. An tially ofz-chromium 0.1v to 2 parts, copper 24 to 50 parts, zinc 10 to .18 parts, and silver not over15 parts A, gold alloy consisting essentially of 40 to 60 0 gold, together with 60 to 40% of an alloy of 0.1 to 2 parts of chromium, 20 to of copper,and 10 to .parts of zinc. l4. A-gol'd" alloy consisting essentially of 40 to 60% gold, together with 60 to 40% of an alloy of 0.1-to 2 parts of chromium, 20 to parts of copper, 10 to 35 parts of zinc, and silver in some amount 'not substantially above 15' parts.

In testimony whereof I afiix my signature.

' THOMAS P. SHIELDS. 

